Evaluation of Options for Remodelling of Upper Jhelum Canal, Pakistan
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Technical Journal, University of Engineering and Technology (UET) Taxila, Pakistan Vol. 20 No. II-2015 Evaluation of Options for Remodelling of Upper Jhelum Canal, Pakistan M. U. Rashid1, A. Latif 2, U. Ghani 3, M. Munir4, T. Sultan5 1Civil Engineering Department, University of Management and Technology, Lahore, Pakistan 2, 5Civil Engineering Department, University College of Engineering & Technology, BZU Multan, Pakistan 3Civil Engineering Department, University of Engineering and Technology Taxila, Pakistan 4Water Resources Division, NESPAK, Lahore, Pakistan [email protected] Abstract-The paper develops and implements the performance, present condition, original design and remodeling approach for alluvial irrigation channels. other deficiencies are very important for remodelling The approach mainly includes in-depth analysis of and modernization of any irrigation system. Shakir and original/existing design parameters, identification of Khan [ii] critically investigated the previous structural existing condition of channel and hydraulic structures interventions for their viability and effectiveness for along with their problems, evaluating different options Marala Ravi Link Canal in Pakistan. The enhancement and finalizing the remodeling parameters by of crest level was also checked and found that it was emphasizing hydraulic, structural and economic effective in reducing sediment intake of MR Link consideration. Upper Jhelum canal in Pakistan was Canal to some extent but did not make any impact in selected as case study channel. The condition survey of reducing the sediment entry to its offtakes including channel was conducted which showed that it was facing Upper Chanab Canal. The sediment management multiple problems i.e. excessive silt deposition, erosion problems of Marala Barrage were also reviewed in the of banks, inadequate freeboard, side embayment and study. Different operational scenarios of Upper Swat widened channel section. The channel was unable to Canal (USC) were investigated and quantified based on run at the design discharge and therefore required fixed frequency operation. Tariq and Latif [iii] remodelling. The reasons for multiple problems were suggested operating the channel at 8090% of the design diagnosed during the study. The analysis showed that discharge during May to July, and 7590% of the design the viable approach for remodeling of subject canal is at discharge from August to April to reduce water losses enhanced design parameters. Different options were due to high water allowance. developed by varying different hydraulic parameters The important parameter for remodelling of and possible economical solutions were analyzed using irrigation channels change in concept, structure and different approaches to suggest the most suitable design. It considers modification in technology, remodelling strategy for UJC. The existing parameters techniques and future consideration of future needs of with minimum change became basis for re-designing of operation and maintenance [iv]. The provision of food the channel by different approaches i.e. Lacey's regime and fibre requirement of people is one of the challenges theory, Manning's formula and Tractive force method. of this century. To fulfill these basic needs of rapidly Sensitivity analysis was also carried out to finalize the growing population water resources and irrigation design parameters emphasizing hydraulic, structural system to efficiently take water up to fields are utmost and economical consideration. The remodelling of UJC important. The Indus Basin Irrigation System (IBIS) as per recommended parameters will ensure increased being the largest contiguous irrigation system of the agriculture and power benefits and enhance world, comprises of 12 inter river link channel, 45 canal conveyance efficiency. systems, about 100,000 tertiary channels, 16 barrages and 3 major reservoirs including Mangla, Tarbela and Keywords-Upper Jhelum Canal, Remodelling, Alluvial Chashma. The IBIS commands cultural command area Channel, Canal Problems of 14 million hectares. Total length of primary, secondary and tertiary channels are 56128 km. IBIS I. INTRODUCTION utilizes 51.3 billion cubic meter (BCM) groundwater pumped through more than 800,000 tube-wells to add- Remodelling of irrigation channels is a process of on the canal supplies [v]. restoring or modernization of existing system The importance of efficient use of irrigation water including all hydraulic structures at same/modified is necessarily increasing as the world population is design parameters. Food and Agriculture Organization increasing. At this stage the country would need more (FAO) [i] discussed that detailed diagnosis including food and fibre to meet the needs of growing 1 Technical Journal, University of Engineering and Technology (UET) Taxila, Pakistan Vol. 20 No. II-2015 population. This shortfall can be met either by process for Pakistan and other countries of the world. constructing new reservoirs or irrigation water Some theories of designing of irrigation channels are management at canal command level [vi]. Irrigation available in literature i.e. Lacey's regime method, water management includes improvement of physical Tractive force method and Manning's formula. infrastructure for distribution of water from source to However, the topic of remodelling and rehabilitation of the crops and water management at the farm level [vii]. alluvial channels also desires practical and hands on Shakir et al. [viii] suggested optimization measures for experience of problems solving and does not much improving water management in Lower Jhelum Canal available in literature. The objectives of this study are i) command in Pakistan which includes enhancing to develop approach/methodology for remodeling of productivity by using crops having higher values and irrigation channels by consulting literature and yields, enhancing conveyance efficiency, adopting practical experience and ii) to apply the developed conservation techniques including bed-furrows, laser approach to remodelling of Upper Jhelum Canal, land leveling, zero tillage and on-farm water Pakistan (case study channel). management. The structural measures identified for improving canal management includes rationalization II. APPROACH/METHODOLOGY FOR of canal capacities in keeping with the current water REMODELING OF IRRIGATION CHANNELS requirements and availability, rehabilitation and remodeling of canal along with its hydraulic structures, The approach developed for remodelling of restoration of prism, raising and strengthening of canal alluvial irrigation channels is as follows: banks and lining of distributaries and minors may lead · In-depth analysis of original/existing design towards optimization of irrigation system of LJC approaches and parameters command. FAO [ix] presented detailed methodology for · Conduct condition survey to access the existing modernization of medium to large irrigation canal condition of channel along with hydraulic systems for improving performance. The strategy was structures and access the reasons for developing developed for analyzing channel optimization on the problems basis of Mapping System and Services for Canal · Develop and evaluate different options for Operation Techniques (MASSCOTE). During the remodeling process of remodeling and modernization, the · Selection of parameters for remodelling of expectations and achievements had to be kept at irrigation channel including design discharge, realistic and practical level. The most economical and longitudinal slope and water levels, bed width and easy-to-implement options were selected to start the depth process of modernization. Irrigation system · Design of irrigation channel by different methods management includes equitable and efficient and sensitivity analysis to finalize the design distribution of water. Computation of irrigation parameters demands and matching water supplies are also very · Finalize the remodeling approach based on important for successful irrigation system. In addition, hydraulic, structural and economic consideration irrigation system should be kept in operating condition throughout the season to achieve the desired objectives. III. CASE STUDY OF UPPER JHELUM CANAL Shakir and Nasir [x] reviewed the problems of Upper (UJC) Chenab Canal in Pakistan. Water availability studies were carried out to ensure the reliability of enhanced Upper Jhelum Canal (UJC) offtakes from Mangla water for irrigation, power and other benefits. It was head works of Jhelum River. It was designed in 1904 suggested that the economical solution for remodelling and commissioned in 1915 primarily as a feeder of the channel was by increasing its water depth instead channel to supplement the supplies of Khanki of enhancing the bed width. It will reduce the cost of headworks at Chanab River for Lower Chanab Canal remodelling of hydraulic structures of UCC. The system. It has total length of 142 km and original design opinion of users through Farmer Organizations (FO) discharge was 12800 cusecs. Its gross and culturable should be considered for devising and implementation command areas are 642447 and 603749 acres of remodelling projects [xi]. FO participation should be respectively. However, the channel was redesign in ensured while computing design of outlets, 1941. It also supplies water for two Hydro power constructing and remodelling channels along with their stations namely Rasul and Shadiwal having power commissioning for monitoring and ensuring equitable